Gaming apparatus, system and method

ABSTRACT

A gaming apparatus configured to provide a main game and being capable of triggering at least one game event includes a component for storing a main game wager value. A player operable input means provided by the apparatus is operable to allow a player to place a wager which is supplementary to the wager placed on the main game and which has a value which is variable by the player in independence of the main game wager value. A processor is responsive to the supplementary wager value so as to determine a characteristic of the game event.

FIELD OF THE INVENTION

The present invention relates to gaming apparatus, systems and methods. It relates for example to electronic gaming machines and to networked gaming systems, such as Internet-based gaming systems.

BACKGROUND OF THE INVENTION

Gaming machines have been a popular form of entertainment for many years. This popularity has been enhanced with the advent of electronic gaming machines and computer-based gaming systems, such as are provided over the Internet.

Many different types of game are playable on such gaming machines. They include for example standard slot-machine type games with spinning reels, poker machines, keno, bingo, blackjack, roulette, pachinko and the like.

A user will typically place a bet to begin a game, and will win or lose based upon the rules of the game.

While such games provide users with enjoyment, the need exists for alternative gaming systems in order to maintain or increase player enjoyment.

SUMMARY OF THE INVENTION

According to a first aspect of the invention there is provided a gaming apparatus configured to provide a main game and being capable of triggering at least one game event, the gaming apparatus including:

a component for storing a main game wager value;

a player operable input means being operable to allow a player to place a wager which is supplementary to the main game wager, a value of the supplementary wager being variable by the player in independence of the main game wager value; and

a processor responsive to the supplementary wager value so as to determine a characteristic of the game event.

In an embodiment the player operable input means is further operable to allow the player to vary the supplementary wager value.

In an embodiment the game event is associated with the main game. For example, the game event could be triggered by a bet placed on the main game.

In an embodiment the player operable input means is operable to allow the player to vary the supplementary wager value from either a wager value previously selected by the player or an initial supplementary wager value determined by the gaming apparatus.

In an embodiment the initial supplementary wager value is associated with a denomination setting for the gaming apparatus.

In an embodiment the gaming apparatus further comprises an indicator for providing to the player information indicative of the characteristic. The information may be adjusted dynamically in response to an adjustment of the supplementary wager value.

In an embodiment the game event includes awarding a bonus game. The bonus game may, for example, have a higher return to player percentage or associated worth than the main game. In another embodiment the game event may include one or more free games or reel re-spins.

In an embodiment the characteristic is a probability of the game event being triggered in association with (e.g. before, during or after) play of the main game.

In an embodiment the processing means is configured to determine the probability such that the probability increases in response to an increase in the supplementary wager value.

In an embodiment the gaming apparatus is capable of triggering a plurality of different game events and wherein the characteristic defines a subset of said plurality that are triggerable during the game.

In an embodiment the player operable input means is operable to adjust the supplementary wager value in predefined increments and wherein each increment is associated with inclusion of a different number of game events within the subset.

In an embodiment the gaming apparatus is configured to allow players to place a plurality of supplementary wagers, with each wager associated with a different characteristic of the game event.

In accordance with a second aspect there is provided a method of gaming in which at least one game event is capable of being triggered, the method comprising:

storing a main game wager value for play of a main game;

allowing a player to place a wager which is supplementary to the main game wager, a value of the supplementary wager being variable by the player in independence of the main game wager value; and

determining a characteristic of the game event responsive to the supplementary wager value.

In an embodiment the supplementary wager value is variable from either a wager value previously selected by the player or an initial supplementary wager value.

In an embodiment the method further comprises providing the player with an indication of the characteristic and wherein the indication is varied in response to a variation of the supplementary wager value.

In an embodiment the game event includes awarding a bonus game.

In an embodiment the characteristic is a probability of the game event being triggered during play of the main game.

In an embodiment the probability increases in relation to the supplementary wager value.

In an embodiment a plurality of different game events are triggerable during the game and wherein the characteristic defines a subset of said plurality.

In an embodiment the method further comprises allowing the player to adjust the supplementary wager value in predefined increments and wherein each increment is associated with inclusion of a different number of game events within the subset.

In an embodiment the method further comprises displaying play of the game on an electronic gaming apparatus.

In accordance with a third aspect there is provided a method of gaming comprising:

allowing a player to place a supplementary wager on a game, a value of the supplementary wager being variable by a player in independence of a base wager value, such that a probability of triggering a feature game in the game is related to the supplementary wager value.

In an embodiment the method further comprises displaying the probability resulting from the varied supplementary wager value to the player prior to initiating play of the game.

In accordance with a fourth aspect there is provided a method of gaming comprising:

providing a player with an opportunity to place a supplementary wager on a game, the supplementary wager operable to allow a game event to be triggerable during play of the game;

displaying a probability of triggering the game event based on a default supplementary wager value; and

allowing the player to vary the default supplementary wager value in independence of a base wager value, to thereby increase or decrease the probability of triggering the game event during the game.

In accordance with a fifth aspect there is provided a gaming apparatus comprising:

a player input module arranged to allow a player to place a supplementary wager on a game, a value of the supplementary wager being variable by the player in independence of a base wager value such that a probability of triggering a game event in the game is related to the supplementary wager value; and

a display arranged to display play of the game.

In accordance with a sixth aspect there is provides a gaming apparatus configured to provide a main game and being capable of providing at least one optional game feature, the gaming apparatus including:

a component for storing a main game wager value;

a player operable input means being operable to allow a player to place a supplementary wager on the game, a value of the supplementary wager being selectable by the player in independence of the main game wager value; and

a processor responsive to the supplementary wager value so as to determine whether to provide at least one game feature in a main game.

In an embodiment the at least one game feature is a guarantee that a guaranteed feature event will trigger when a set amount of gameplay is reached without a monitored feature event having been triggered within the set amount of gameplay.

In an embodiment the at least one optional game feature is a method of awarding a bonus prize to a player, the method including the steps of:

defining a threshold value;

conducting a feature event, or part thereof, so as to determine a feature event win value, wherein the feature event includes the provision of a plurality of feature games; and

comparing the feature event win value to the threshold value and, if the feature event win value is less than or equal to the threshold value, awarding the bonus prize to the player.

In an embodiment the processor is configured to determine not to provide the guarantee and not to provide the method of awarding a bonus prize if the supplementary wager value is equal to a first value.

In an embodiment the processor is configured to determine to provide the guarantee and not to provide the method of awarding a bonus prize if the supplementary wager value is equal to a second value.

In an embodiment the processor is configured to determine not to provide the guarantee and to provide the method of awarding a bonus prize if the supplementary wager value is equal to a third value.

In an embodiment the processor is configured to determine to provide the guarantee and to provide the method of awarding a bonus prize if the supplementary wager value is equal to a fourth value.

In accordance with a seventh aspect there is provided computer program code which when executed by a computing system implements the method as described in accordance with any one of the second, third or fourth aspects.

In accordance with an eighth aspect there is provided a computer readable medium comprising the computer program code as described in accordance with the seventh aspect.

An embodiment of the system further includes a central control for running a gaming algorithm, and a plurality of remote clients in communication with the central control over a communications network, the remote clients including screens for the display of information to players.

Embodiments of the present invention may be applied to any suitable type of gaming system or platform. It can apply to stand-alone gaming apparatus, e.g. electronic gaming machines, such as video gaming machines, to gaming machines that are linked together, e.g. via a network such as an intranet, and/or to gaming systems provided through computing or other electronic devices, e.g. personal computers, PDAs, mobile telephones, digital televisions, and the like, e.g. over the Internet or other communications networks.

Embodiments may be applied to gaming apparatus that play any suitable game, e.g. slot-machine type games, poker, keno, blackjack, bingo, roulette, pachinko, or the like.

In some networked embodiments of the invention, the central control may conduct the games and manage the accounting and the like, and a number of remote terminals/clients merely provide the user input and display mechanisms. In other networked embodiments of the invention, the control of the games and various other features may be carried out at the remote terminals, or may be split between the central control and the remote terminals.

It should be noted that any of the features of any of the aspects mentioned above may be combined with any other features mentioned above, as appropriate.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

Features and advantages of the present invention will become apparent from the following description of embodiments thereof, by way of example only, with reference to the accompanying drawings, in which:

FIG. 1 is a block diagram of gaming apparatus according to one embodiment of the present invention;

FIG. 2 is a schematic of a game controller according to an embodiment;

FIG. 3 is a flow diagram of a gaming control process in accordance with an embodiment of the present invention; and

FIGS. 4 a, 4 b and 4 c are example screen shots illustrating an embodiment of the invention.

DETAILED DESCRIPTION

In an embodiment a game controller of a gaming device comprises a display module operable to provide the display of a main game on an electronic gaming machine and a trigger module being capable of triggering at least one game event. A player operable input means is operable to allow a player to place a wager which is supplementary to the wager placed on the main game and which has a value which is variable by the player in independence of the main game wager value. A processing module of the game controller is responsive to the supplementary wager value so as to determine a characteristic of the game event.

General Construction of a Gaming System

Referring to FIG. 1 there is shown a gaming apparatus, which in this case takes the form of an electronic gaming machine (EGM) 1, and which includes various standard components, such as a game controller 2 for controlling the operation of the EGM 1 and the games run on it, a note/coin/token input 3 for receiving bets, a note/coin/token output 4 for paying out winnings, one or more displays 5 for displaying game screens, and player input means 6 for allowing user interaction, which may include e.g. buttons 7 and/or which may e.g. be provided as part of the display 5 in a touch-screen type manner. The EGM 1 also includes a player tracking and marketing means 9 having a reading device (e.g. a card scanner for reading a smart card or other form of portable storage medium capable of being read by the card scanner) which communicates with a remote server for providing player tracking and loyalty type functions, as is well understood in the art. Additional hardware may be included as part of the EGM 1, or hardware may be omitted as required by the specific implementation.

In one form the EGM 1 may be a stand-alone machine. In another form, the EGM may be networked with other EGMs and/or a control centre via a suitable communications network 8, such as a LAN and/or WAN, in order to play networked (e.g. intranet or Internet) games, such as a linked jackpot. It will be appreciated that the EGM 1 may include an appropriate communications interface, such as a network card, for communicating over the communications network 8.

In use, the EGM 1 will display an initial gaming screen on the display 5. A player will insert bank notes, coins and/or tokens into the EGM input 3, and will press a button 7 to initiate play of the main game provided by the EGM 1. How matters then proceed will depend on the type of main game being played. For example, FIG. 4 illustrates a game screen from a slot machine-type game, in which the EGM 1 displays virtual reels 10 of symbols 11, and spins and stops these reels 10 in various win and lose symbol combinations on one or more paylines 12 in accordance with a stored gaming algorithm and a random number generator. In an alternative embodiment (not illustrated) the main game is a poker-type game, in which a player will receive a number of cards with which to play for a winning hand. It will be appreciated that other types of main games may be provided, such as keno, blackjack, bingo, roulette, pachinko, or the like. For the purposes of this detailed description, the main focus shall be upon an embodiment providing a slot machine-type main game.As used in this document, including in the claims, the terms “random”, “randomly”, “randomized”, and the like, are to be construed as connoting either a purely random process or a “pseudo-random” process. An example of a pseudo-random process includes the determination by a computer processor of a pseudo-random number in response to an output of a digital clock.

The player may interact via the buttons 7, so as e.g. to spin or hold reels and otherwise play the main game. A common element will be win events, e.g. particular symbol combinations that pay out a prize or jackpot.

Also, in order to increase interest, the main game is capable of providing feature events that consist of one or more feature games, which may or may not relate directly to the main game being played, and that generally provide a prize of some sort. These feature events may include for example one or more free games, a re-spin (similar to a free game but with one or more reels held on a slot device), and the chance to play for higher winnings or the like. They may be e.g. luck or skills based. They may be provided as “second screen” features that display on a new screen, and may be extraneous to the main game.

Another way of adding gaming interest is for a main game or a feature event to include one or more wild symbols that can represent more than one type of symbol or card, and so can increase the chances of achieving a winning combination or the like. Similarly, for embodiments in which the main game is a card game, wild cards may be provided.

These win and feature events can be arranged to occur due to the usual operation of the main game randomly or under a particular set of circumstances, e.g. under a set symbol or card combination. They may also occur due to an accumulation of circumstances across a number of games, and may occur due to the condition of a device supplemental to the EGM 1 itself, e.g. they may relate to jackpot wins in linked jackpot systems comprising a plurality of EGMs under a central control.

FIG. 1 illustrates an essentially stand-alone EGM (albeit with the potential for networked connectivity). However, in an alternative embodiment the system may be implemented over a distributed architecture where some of the individual EGM modules are implemented remotely. For example, in one particular form, a central control computer which is located remotely of the EGM may implement a controller which controls some or all of the game play functionality (i.e. such that the EGM essentially operates as a remote client arranged to provide audible and/or visual gaming information to a player and allow player interaction with the central control computer). A plurality of EGM clients may be in communication with the central control computer over a communications network such as a local area network and/or a wide area network. In an alternative embodiment, the game play functionality may be implemented by both the EGM and central control computer such that they collectively provide a game controller.

The central control computer has access to associated memory and storage devices. The central control computer also has access to ccomputer executable code for instructing the central control computer to run the gaming algorithm that performs the embodiment of the inventive method. In one embodiment the ccomputer executable code is in the form of software and associated data, which are stored upon a computer-readable medium in the form of one or more compact disks. Alternative embodiments make use of other forms of digital storage media, such as Digital Versatile Discs (DVD's), hard drives, flash memory, Erasable Programmable Read-Only Memory EPROM, and the like. Alternatively, the software and its associated data may be stored as one or more downloadable or remotely executable files that are accessible via a computer communications network such as the internet.

Detail of the Game Controller

The game controller 2 of an embodiment is shown in more detail in FIG. 2. For simplicity only those modules (which may be implemented in hardware, software, or a combination of the two) needed to carry out embodiments are illustrated. Other standard and/or non-standard modules may also be implemented for carrying out operation of normal and feature game play functionality. It will be understood that the term “processor” as used herein is to be construed broadly and include within its scope any device that can process gaming algorithms and may include a microprocessor, microcontroller, programmable logic device or other computational device, a general purpose computer, or a server computer. Typically, the gaming algorithms (instructions) are stored as program code in memory 13, which is in data communication with the processor.

In the illustrated embodiment, the game controller 2 includes a processor 20 which is arranged to control play of a main game and further configured to trigger at least one game event. The at least one game event may be triggered during play of the main game or, in alternative embodiments, may be triggered before or after play of the main game. Players may place a wager which is supplementary to the wager placed on the main (referred to as a “supplementary wager”), the value of which affects a characteristic of the at least one game event. The value of the supplementary wager is variable by the player in independence of the main game wager value. The supplementary wager value may, for example, be varied by the player in linear increments (e.g., 10 cents, 20 cents, 30 cents, etc.) or non-linear increments (e.g., 10 cents, 1 dollar, 5 dollars, 10 dollars), with each increment having a different effect on the characteristic. Alternatively, the value may be set to any particular value desired by the player, with the effect on the characteristic being adjusted by the game controller accordingly.

To facilitate the above functionality, the processor 20 implements a number of modules, based on program code stored in memory 13. A supplementary wager module 22 is operable to determine a characteristic of the game event based on the variable supplementary wager (e.g. input by the player using the player input means 5). As will be elucidated in subsequent paragraphs, the supplementary wager value(s) can be adjusted by the player prior to commencement of game play to affect the characteristic of the game event. An indication module 24 is arranged to provide to the player information indicative of the characteristic, e.g. by way of the EGM display 5 (i.e. and under control of the display controller 26).The indication module may be configured to depict the information in a numeric format or a graphical format, dependent on the desired implementation. The processor 20 also implements a trigger module 28 arranged to trigger the game event and an outcome determiner 30 for determining game (and game event) outcomes, with the aid of a RNG 32.

A specific embodiment will now be described with additional reference to the flowchart of FIG. 3 and example screen shots of FIGS. 4 a, 4 b, 4 c (which depict a reel-type game implementing the variable side bet functionality). The flowchart assumes that the game event is a feature game in the form of a bonus game called “Jackpot Pyramid” which provides the player with an opportunity to win one or more bonus prizes, and potentially a jackpot prize(although it will be understood that other game events are equally applicable as described in more detail in subsequent paragraphs) and which is triggerable following play of the main game. Players can adjust a value of a supplementary wager to affect the likelihood that the Jackpot Pyramid game will be triggered following the conclusion of a play of the main game.

At step S1 a player places a main game wager in order to play a game in the form of a reel game on the EGM 1. For the sake of a running example, we shall assume that the amount of the trigger bet was $2.00(or the equivalent in credits) and that this bet was placed on 25 lines of the main slot machine game. The supplementary wager module 22 then sets a default supplementary wager value and an associated probability for triggering the feature based on that value. Both the default value and associated odds are displayed to the player (see steps S2 and S3). According to the illustrated example, the default supplementary wager value is set at $0.25 with the chance of triggering the feature being 1 in 30. An example screen shot displaying the default value and associated odds is shown in FIG. 4 a (as shown to the player in the supplementary wager window 45 at the top right of screen). The default supplementary wager value may be determined based on the machine denomination settings (e.g. a 1 cent machine has a 1 cent supplementary wager default value), a parameter associated with the main game wager, or alternatively could be set as some predefined fixed value (e.g. $0.05). It will also be appreciated that in a particular embodiment the default supplementary wager value may represent a minimum value for the supplementary wager.

At step S4, the player is provided with an opportunity to vary the default supplementary wager value so as to increase or decrease the associated probability of triggering the feature game. This may be achieved by selecting the up arrow 47 or down arrow 49 to increase or decrease the supplementary wager value, respectively. In a particular embodiment, each press of the arrow may cause the wager value to increase or decrease by a particular increment (e.g. 1 c), depending on the desired implementation. In response to determining that the player has adjusted the value (see step S5), the new adjusted value is stored in memory 13 and the process returns to step S3, for calculating the associated trigger odds for the new stored value. For example, with reference to FIG. 4 b, the player has decreased the value of the supplementary wager to $0.10 (i.e. by selecting the down arrow 49 an appropriate number of time), resulting in reduced odds of 1 in 75 for triggering the feature. In FIG. 4 c, the player has elected to increase the supplementary wager value to $1.25 having the effect of increasing the chance of triggering the feature to 1 in 6. The process loops until the player locks in the supplementary wager value (e.g. by hitting the “bet” button). At that time the game controller 2 initialises the game variables and parameters (step S7) and game play commences at step S8, with the player specified odds. It will be appreciated that the feature game may not necessarily be triggered during play of the main game and instead could trigger either before or after play of the main game. For example, where the feature is a jackpot prize, the trigger module 30 may cause the jackpot to be awarded prior to commencing the main game reel spin.

In an alternative embodiment to that described above, the game event may not relate to a feature game but instead be associated with one or more main game awards or parameters (hereafter “special awards”), with the characteristic being related to the worth, type and/or number of special awards that are provided. A feature game could still be triggered during game play with an associated trigger probability tied to the base wager amount, or the like. As previously mentioned, in particular embodiments, players may increase (or decrease) a value of the supplementary wager in predefined increments, with each increment being associated with a particular combination of special awards that are provided in the main game. An example look-up table for a game controller illustrating how such an embodiment may operate in practice is shown on the next page. The “Feature Guarantee” and “Win-Win” special awards are described in Australian Patent No's 2004281073 and 2009222486 respectively, which are each incorporated herein by reference.

TABLE 1 Example Look-Up Supplementary Wager Value Special Award included in Main Game None None $0.25 Feature Guarantee $0.75 Feature Guarantee and Win-Win $1.50 Feature Guarantee, Win-Win and 15 extra reel spins of feature game (if triggered)

Thus, according to the above example, the greater the value of the supplementary wager selected by the player, the greater the number of special awards that are incorporated into the game play. It will be appreciated that the increments may be other than fixed dollar amounts and could instead, for example, be a multiple of the base wager value (expressed in absolute terms, per line wagered, or otherwise). In a slightly alternative embodiment, the number of special awards may remain fixed and instead the associated worth increased with the supplementary wager value. For example, the award could be that one or more multiplier symbols are made available in the main game with the actual multiplier values increasing with the supplementary wager value. It will be appreciated that the number and type of award(s), as well as the corresponding supplementary wager values are not limited to those outlined above and any appropriate combination of the three above variables may be utilised depending on the desired outcome.

The adjustment of the supplementary wager value for the special award may also be configured to influence the odds of triggering the feature as in the previous example. Alternatively, the game may require the player to place an additional supplementary wager to influence the associated odds for the feature. An example look-up table for such an embodiment is shown on the next page.

TABLE 2 Example Look-Up Probability of First Special Award Second Triggering Supplementary included in Supplementary feature game Wager Value Main Game Wager Value (%) None None None 0 $0.25 Feature Guarantee $0.10 .013 $0.75 Feature Guarantee $0.25 .033 and Win-Win $1.50 Feature Guarantee, $1.25 .167 Win-Win and 5 extra free games in feature game (if triggered)

It will be appreciated that the game controller may be arranged to store any number of different supplementary wagers, each associated with one or more different game event characteristics.

Furthermore, it will be appreciated that the game event may relate to any form of event or game play parameter, including features or prizes that can be triggered independently or in dependence of (i.e. in association with) the main game. For example, an independently triggered event may comprise of an entirely separate game in which a jackpot prize may be awarded and which is triggered based on some triggering technique which is not in any way tied to an outcome of the main game. Alternatively, the event may relate to a feature which forms part of the main game with the characteristic relating to the inclusion, exclusion or adjustment of that feature (e.g. inclusion of special symbols such as wild symbols as the supplementary wager value increases). In one particular embodiment the supplementary wager may be placed on a side game which is displayed on the same screen display as the main game and which is played either in sequence or concurrently with the main game. It will be appreciated that the side game could also be played on a separate screen to the main game, for example on a topper of the EGM, or on a display separate of the EGM and which forms part of a networked gaming system. In one particular embodiment the supplementary wager value may influence a worth (e.g. a return to player percentage) of a prize awardable as part of the game. For example, as the supplementary wager value increases so too does the value of a jackpot prize which may be awarded as part of a bonus game.

In one particular embodiment, the placement of a supplementary wager is compulsory in order to play the game. In this case, the value of the minimum supplementary wager may be fixed (e.g. $0.01 for a 1 cent machine), tied to the main game wager (e.g. 1 times the bet per line wagered in the main game), or associated with some other game play parameter. In another embodiment, supplementary wagers may be optional with the player qualifying for the associated feature(s) only once the supplementary wager or wagers have been placed.

It will be appreciated that techniques other than those described above may be utilised for providing an indication of the game event characteristic (i.e. as affected by the supplementary wager value selected by the player). For example, where the characteristic relates to the odds for triggering the event, the display may simply provide an indication that the odds are increased or decreased based on the player selected supplementary wager value without displaying the actual resultant odds. Alternatively, the machine may be programmed to provide no indication as to what effect the variation in the supplementary wager value has on the characteristic.

It is to be understood that various alterations, additions and/or modifications may be made to the parts previously described without departing from the ambit of the present invention, and that, in the light of the above teachings, the present invention may be implemented in software, firmware and/or hardware in a variety of manners as would be understood by a person skilled in the art. 

The claims defining the invention are as follows:
 1. A gaming apparatus configured to provide a main game and being capable of triggering at least one game event, the gaming apparatus including: a component for storing a main game wager value; a player operable input means being operable to allow a player to place a wager which is supplementary to the main game wager, a value of the supplementary wager being variable by the player in independence of the main game wager value; and a processor responsive to the supplementary wager value so as to determine a characteristic of the game event.
 2. A gaming apparatus according to claim 1 wherein the player operable input means is further operable to allow the player to vary the supplementary wager value.
 3. A gaming apparatus according to claim 2 wherein the player operable input means is operable to allow the player to vary the supplementary wager value from either a wager value previously selected by the player or an initial supplementary wager value determined by the gaming apparatus.
 4. A gaming apparatus according to claim 3 wherein the initial supplementary wager value is associated with a denomination setting for the gaming apparatus.
 5. A gaming apparatus according to claim 1, further comprising an indicator for providing to the player information indicative of the characteristic and wherein the information is adjusted in response to an adjustment of the supplementary wager value.
 6. A gaming apparatus according to claim 1 wherein the game event includes awarding a bonus game.
 7. A gaming apparatus according to claim 1 wherein the game event includes one or more free games.
 8. A gaming apparatus in accordance with claim 1 wherein the characteristic is a probability of the game event being triggered in association with the main game.
 9. A gaming apparatus according to claim 8 wherein the processor is configured to determine the probability such that the probability increases in response to an increase in the supplementary wager value.
 10. A gaming apparatus according to claim 1 wherein the gaming apparatus is capable of triggering a plurality of different game events and wherein the characteristic defines a subset of said plurality that are triggerable in association with the game.
 11. A gaming apparatus according to claim 10 wherein the player operable input means is operable to adjust the supplementary wager value in predefined increments and wherein each increment is associated with inclusion or exclusion of a different number of game events within the subset.
 12. A gaming apparatus according to claim 1 wherein the player operable input means is operable to allow players to place a plurality of supplementary wagers, with each wager being associated with a different characteristic of the game event.
 13. A method of gaming in which at least one game event is capable of being triggered, the method comprising: storing a main game wager value for play of a main game; allowing a player to place a wager which is supplementary to the main game wager, a value of the supplementary wager being variable by the player in independence of the main game wager value; and determining a characteristic of the game event responsive to the supplementary wager value.
 14. A method according to claim 13 further comprising providing the player with an indication of the characteristic and wherein the indication is varied in response to a variation of the supplementary wager value.
 15. A method in accordance with claim 13, wherein the game event comprises awarding a bonus game or jackpot prize such that the determined characteristic is a probability of triggering the game event during play of the main game.
 16. A method according to claim 16, wherein the probability increases in relation to the supplementary wager value.
 17. A method according to claim 13, wherein a plurality of different game events are triggerable during the game and wherein the characteristic defines a subset of said plurality that will apply for the wagered game.
 18. A method according to claim 17 further comprising allowing the player to adjust the supplementary wager value in predefined increments and wherein each increment is associated with the inclusion of a particular game event within the subset.
 19. A method of gaming comprising: providing a player with an opportunity to place a supplementary wager on a game, the supplementary wager operable to allow a game event to be triggerable during play of the game; displaying a probability of triggering the game event based on a default supplementary wager value; and allowing the player to vary the default supplementary wager value in independence of a base wager value, to thereby increase or decrease the probability of triggering the game event during the game.
 20. Computer readable medium implementing computer program code which, when executed by a computing system, implements the method according to claim
 13. 